Fig. 2.

(A) Bacterial burden in the lungs of MCP-1^−/− mice following E. coli infection (10⁶/mouse). Lungs were collected from control and infected groups of mice at the designated times and homogenized, and the bacteria were enumerated (n = 5 to 6 mice/group). *, significant difference between knockout and WT mice (P < 0.005). Data shown are a representation of 3 individual experiments. (B and C) Cellular infiltration in the lung in MCP-1^−/− mice against E. coli. Mice were inoculated with E. coli (10⁶ CFU/mouse), BALF was obtained at 6 and 24 h postinfection, and cell enumeration was performed to determine neutrophil and macrophage infiltration to the lung (n = 4 to 5 mice/group; P < 0.005; data are a representation of 3 individual experiments). (D) Lung histology in MCP-1^−/− mice following E. coli infection. Mice were inoculated with E. coli (10⁶ CFU/mouse), and lungs were obtained at 24 h postinfection. This picture is representative of 3 separate mice with identical results.